Updating a jailbroken iphone 4s

I want to just update the iphone to the latest ios, not bothered about losing the jaillbreak.
Can anyone help on this, ive tried to do it via the phone update and via itunes but keep getting error 3004 messages.

Thanks

Have you tried doing a restore in DFU mode, and then upgrading?

DFU mode is the way to go and check that your hosts file doesmt contain any apple entries. You could always use a clean hosts file to be sure then swap it back after. Sometimes different cables and USB ports help but DFU sorts most if these errors. Also use latest iTunes.

Tried the dfu mode didn't work but I didn't check the hosts. Will try that again. Thanks guys

Worked a treat, it was the hosts file, anyone else wanting to do this and getting error's, heres how to edit the hosts file.

Close iTunes
Start –> Programs –> Accessories
Run Notepad or WordPad (as administrator on windows 7)
Click “Open..” from File menu.
Browse to Windows/System32/drivers/etc
In "files of type:" select all documents
Open "hosts"
Either delete all line that has "gs.apple.com", or add a "#" sign at the beginning of the line to comment it out
Hit Save
Reboot computer for changes to take effect.
Visit http://gs.apple.com/ to verify that the hosts file is pointing to Apple and not Cydia.
Restore your device.